I am trying to replace a ceramic cartidge in some bathroom taps. I cannot get the head gear off. Taps are about 6 years old. Any tips on how to get them off - my presumption is they should just pull off the nylon / plastic sleeve on the cartridge head. I have tried penetrating lubricant spray to no avail

Lawrence,
You could try levering under the heads with a wide blade screwdriver, use a cloth pad to protect whatever you find to lever onto. If they do not lever off there must be a fixing screw holding them on - you've just got to find it.
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